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6 CHAPTER TWO RESEARCH ISSUES REGARDING PSYCHOACTIVE CHEMICALS SYNTHESIS PROBLEM STATEMENT APPLIED Schedule II controlled substances include opioids, often pre- TO THE LITERATURE REVIEW scribed to treat pain, and stimulants, sometimes prescribed for narcolepsy or Attention Deficit Hyperactivity Disorder This chapter outlines four issues that set the stage for litera- (ADHD). Depressants may be prescribed to alleviate anxiety ture review of chemical substances. This chapter also briefly or for treatment of certain sleep disorders such as insomnia, describes the effects of alcohol (ethanol) on performance and their controlled substance classification varies based on (about which much is known) to provide a baseline against the factors identified earlier. Although there are concerns about which to judge research findings about effects of other how such drugs may affect driving performance, in some chemicals and drugs. Subsequent chapters report on published instances individuals afflicted by certain medical conditions findings describing the principal categories of psychoactive may actually drive better when using the prescribed drugs, chemicals of direct pertinence to commercial driver perfor- presumably because the drug treatment works to assist patients mance and health. Chapter three reviews sleep-promoting with their particular maladies (Barkley et al. 2005). substances, including hypnotics, and treatment medications prescribed for insomnia and other sleep disorders, as well as With some generalization, the effects of drugs can be antihistamines often used to promote sleep. Chapter four discussed in terms of drug types or drug categories. For covers stimulants and alertness compounds; those meant example, NIDA classifies illicit drugs into seven major drug to keep one awake while working. Chapter five reviews categories on the basis of their psychoactive effects on the dietary, nutritional, herbal, and energy boost compounds, or central nervous system (CNS). These classes and sample drugs simply "supplements" that contain psychoactive components. within each class (derived from NIDA documents, 2006) are Appendix A presents information on other psychoactive chem- listed in Table 1. Narrative sections in this synthesis focus on ical substances within the U.S. National Institute of Drug several but not all of these drug categories. Abuse's (NIDA's) list of addictive illicit drugs (drugs of abuse such as marijuana and cocaine), for which there is literature The American Medical Association has published fairly on performance effects, including research on the effects of extensive information on the driving-related effects of legally such chemicals on driving performance. Although illicit drugs prescribed drugs (AMA 2003), as did the U.S. National and other chemical substances do not warrant a viable role Highway Traffic Safety Administration (NHTSA 2005) and for operational use by commercial drivers, their occasional use the International Council on Alcohol, Drugs and Traffic by some commercial drivers is confirmed in employer random Safety (ICADTS 2006). In reviewing such informative lists, drug screening tests of drivers and by government-sponsored NHTSA's David Shinar stated that "short of saying that all crash and accident investigation reports and statistics from drugs are bad (and even that statement is not true) it is difficult numerous countries, including the United States. to have a general discussion about drug effects on perfor- mance" (Shinar 2007b). This he says is because different drugs DRUG DEFINITIONS AND CATEGORIZATION have different pharmacological properties that cause differ- ent physiological and physical signs and symptoms, and The first issue is one of determining how to categorize or label consequently have different effects on attitudes and behavior the numerous classes of psychoactive chemical substances in general, and on driving-related attitudes and behaviors in in this report. Chemicals, medications, or drugs could be particular. Shinar says it is nearly impossible and (fortunately) identified in the way that medical practitioners consider them, unnecessary to discuss separately each of the drugs in the as potential treatments for diseases, illnesses, and medical categories identified in the governmental sanctioned lists maladies or as prescription drugs or alternatively as non- mentioned above (Shinar 2005, 2007b). prescription treatment drugs. Some drugs also could be clas- sified as "controlled substances," which refers to their potential The FMCSA has provided guidance for medical examiners for abuse and physical as well as psychological dependence of commercial drivers and rules governing the use of certain [see for example the extensive list of drugs, Schedules I medications by commercial drivers. These are widely distrib- through V, provided by the U.S. Drug Enforcement Admin- uted and available on FMCSA websites, and will be dis- istration (DEA) (CFR Title 21 Chapter II) and the lists of cussed with each medication or substance; however, for most the Food and Drug Administration (FDA)]. Examples of medications the FMCSA has given guidance based on the